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1.
Thi Thanh Nhan Pham Thi Ngoc Lan Nguyen Thi Ha Bui Huu Quan Nguyen Thi Tam Nguyen Van Son Le 《The Journal of Horticultural Science and Biotechnology》2019,94(5):591-598
Catharanthus roseus contains vincristine and vinblastine, which are outstanding drugs for cancer. In the biosynthetic pathways of terpenoid indole alkaloids (TIAs) in C. roseus, deacetylvindoline 4-O-acetyltransferase (DAT) is a key enzyme that catalyses the last reaction of vindoline biosynthesis to form vinblastine and vincristine. In this study, the CrDAT transgene was transferred into the periwinkle by Agrobacterium-mediated transformation and generated transgenic periwinkle lines with an increase in vincristine accumulation. The C. roseus DAT gene was introduced into C. roseus plants and it was confirmed that CrDAT was successfully transferred into the genome of periwinkle plants and efficiently translated to synthesise recombinant DAT protein. Four transgenic periwinkle lines in T1 generation, T1-1, T1-3, T1-6, and T1-7, expressed recombinant DAT protein with the total protein content in the range of 2.86 μg.mg?1 to 5.12 μg.mg?1. Moreover, the vincristine contents of four transgenic lines increased by 1.63?2.48-fold compared to non-transgenic plants, ranging from 6.91 µg.g?1 (fresh weight) to 10.53 µg.g?1 (fresh weight). The T1-1 line had the highest vincristine content. Hence, the overexpression of the recombinant DAT protein can improve the vincristine accumulation of transgenic C. roseus plants.Abbreviation: CrDAT - Catharanthus roseus Deacetylvindoline-4-O-Acetyl Transferase; D4H - Deacetoxyvindoline 4-hydroxylase; ELISA - Enzyme-Linked Immunosorbent Assay Monoterpene indole alkaloid; T0, T1 - Generations of transgenic plants; TIAs - Terpenoid indole alkaloids; WT- The wild-type tobacco plants (non transgenic plant); 35S - Cauliflower mosaic virus 35S promoter 相似文献
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Maria Antonia Machado Barbosa Kacilda Naomi Kuki Pedro Santos Peno Bengala Emilly dos Santos Pereira Angélica Fátima de Barros Sebastián Giraldo Montoya Leonardo Duarte Pimentel 《Journal of Agronomy and Crop Science》2020,206(2):263-276
Environmental conditions influence phenology and physiological processes of plants. It is common for maize and sorghum to be sown at two different periods: the first cropping (spring/summer) and the second cropping (autumn/winter). The phenological cycle of these crops varies greatly according to the planting season, and it is necessary to characterize the growth and development to facilitate the selection of the species best adapted to the environment. The aim of this study was to characterize phenological phases and physiological parameters in sorghum and maize plants as a function of environmental conditions from the first cropping and second cropping periods. Two parallel experiments were conducted with both crops. The phenological characterization was based on growth analyses (plant height, leaf area and photoassimilate partitioning) and gas exchange evaluations (net assimilation rate, stomatal conductance, transpiration and water-use efficiency). It was found that the vegetative stage (VS) for sorghum and maize plants was 7 and 21 days, respectively, longer when cultivated during the second cropping. In the first cropping, the plants were taller than in the second cropping, regardless of the crop. The stomatal conductance of sorghum plants fluctuated in the second cropping during the development period, while maize plants showed decreasing linear behaviour. Water-use efficiency in sorghum plants was higher during the second cropping compared with the first cropping. In maize plants, in the second cropping, the water-use efficiency showed a slight variation in relation to the first cropping. It was concluded that the environmental conditions as degree-days, temperature, photoperiod and pluvial precipitation influence the phenology and physiology of both crops during the first and the second cropping periods, specifically cycle duration, plant height, leaf area, net assimilation rate, stomatal conductance and water-use efficiency, indicating that both crops respond differentially to environmental changes during the growing season. 相似文献
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da Silva Isadora Gonçalves Castoldi Renata de Oliveira Charlo Hamilton César de Souza Miranda Mateus Nunes Thaíssa Dias Cardoso Costa Luciene Lacerda Lemes Ernane Miranda 《Journal of Crop Science and Biotechnology》2020,23(2):191-196
Journal of Crop Science and Biotechnology - The cultivation of sweet corn is expanding in Brazil, but there are serious constraints about the availability of commercial cultivars. The selection of... 相似文献
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旨在估计山下黑猪和鲁莱黑猪正反交F1代杂种优势,筛选出合适的杂交方式,以提高优质肉猪的生产效率,满足人们对于优质猪肉的需求。本研究在山下黑猪(164头)和鲁莱黑猪(69头)及其正(6头山下黑猪♂×25头鲁莱黑猪♀)、反(3头鲁莱黑猪♂×35头山下黑猪♀)交4个群体中测定了生长肥育、体尺外貌(75~110 kg)、繁殖和胴体肉质(90~115 kg)4大类共43个性状,比较了这些性状在群体间的差异,并估计了正反交F1代的杂种优势。结果表明,山下黑猪的生长肥育和体尺性状较好,鲁莱黑猪的繁殖和肉质性状较好,正反交群体介于它们之间。正交群体的繁殖性能优于反交群体,但生长肥育性能比反交差。由于这4个群体的母猪都是纯种,因此繁殖性状没有表现出明显杂种优势。除膘厚、胸椎数、45 min pH和剪切力无显著的杂种优劣势外,大部分胴体性状和肉质性状有明显的杂种劣势。生长肥育性状的杂种优势在正反交群体中的表现不一致,反交群体表现出显著杂种优势,而正交则无明显的杂种优势。本研究估计了山下黑猪和鲁莱黑猪正反交的杂种优势,为筛选山下黑猪和鲁莱黑猪的最佳杂交方式奠定基础。 相似文献
7.
de Almeida Márcia Rodrigues Schwambach Joséli Silveira Vanildo Heringer Angelo Schuabb Fett Janette Palma Fett-Neto Arthur G. 《New Forests》2020,51(2):213-241
New Forests - Adventitious rooting (AR) is an obligatory step for vegetative propagation of commercial woody species. Paper industries have interest in Eucalyptus globulus Labill and its hybrids... 相似文献
8.
Screening of antagonistic Trichoderma strains and their application for controlling stalk rot in maize 下载免费PDF全文
LU Zhi-xiang TU Guang-ping ZHANG Ting LI Ya-qian WANG Xin-hua Zhang Quan-guo SONG Wei CHEN Jie 《农业科学学报》2020,19(1):145-152
Maize is one of the major crops in China, but maize stalk rot occurs nationwide and has become one of the major challenges in maize production in China. In order to find an environment-friendly and feasible technology to control this disease, a Trichoderma-based biocontrol agent was selected. Forty-eight strains with various inhibition activities to Fusarium graminearum, and Fusarium verticillioides were tested. A group of Trichoderma strains(DLY31, SG3403, DLY1303 and GDFS1009) were found to provide an inhibition rate to pathogen growth in vitro of over 70%. These strains also prevented pathogen infection over 65% and promoted the maize seedling growth for the main root in vivo by over 50%. Due to its advantage in antifungal activity against pathogens and promotion activity to maize, Trichoderma asperellum GDSF1009 was selected as the most promising strain of the biocontrol agent in the Trichoderma spectrum. Pot experiments showed that the Trichoderma agent at 2–3 g/pot could achieve the best control of seedling stalk rot and promotion of maize seedling growth. In the field experiments, 8–10 g/hole was able to achieve over 65% control to stalk rot, and yield increased by 2–11%. In the case of natural morbidity, the control efficiency ranged from 27.23 to 48.84%, and the rate of yield increase reached 11.70%, with a dosage of Trichoderma granules at 75 kg ha~(-1). Based on these results, we concluded that the Trichoderma agent is a promising biocontrol approach to stalk rot in maize. 相似文献
9.
不同施氮量下覆膜滴灌玉米相对根长密度模型研究 总被引:2,自引:0,他引:2
为探明施氮量对宁夏引黄灌区覆膜滴灌玉米根长密度(RLD)的影响,设置5个施氮水平和1个对照(CK,不施氮与不覆膜)进行试验,测定玉米RLD,建立不同施氮量下相对根长密度(NRLD)模型,并加以检验。结果表明:不同施氮处理的玉米RLD分布区域均随土层深度的增加而减小,且大部分集中在0~20 cm土层;随着施氮量的增加,RLD分布区域明显扩大; NRLD分布满足三阶多项式函数模型,模拟曲线的决定系数R2为0.951,模型检验结果R2为0.845,均方根误差(RMSE)为0.248,拟合效果好,但该多项式模型不能保证NRLD在相对取样深度Zr为1时达到0,故对玉米NRLD分布多项式模型进行优化。优化模型验证结果显示,各施氮处理RMSE不大于0.308,CK、N0、N1、N2、N3和N4处理的标准化均方根误差分别为0.242、0.193、0.184、0.226、0.208和0.273,R2分别为0.903、0.953、0.920、0.944、0.962和0.898,具有较高的拟合度,解决了NRLD在Zr=1时达到0的问题。本研究可为宁夏引黄灌区膜下滴灌玉米NRLD分布拟合、根系养分吸收和施肥管理提供理论参考。 相似文献
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狂犬病病毒SRV9克隆株核蛋白基因的克隆、表达与特性分析 总被引:4,自引:0,他引:4
根据已发表的狂犬病病毒核蛋白基因序列,设计并合成了一对引物,从SAD株驯化的SRV9。蚀斑株中提取病毒RNA,通过RT-PCR扩增出核蛋白的全长cDNA序列,测序结果显示,其序列与国外报道的SAD母源株序列一致。将核蛋白的cDNA克隆至原核表达载体pET-28b( )中,转化大肠杆菌BL21(DE3)plyss,于30℃1mmol/LIPTG条件下诱导表达,大肠杆菌菌体裂解产物经SDS-PAGE分析,在分子量约为56kDa处出现一新的蛋白带。和预期的目的蛋白分子量相符,Western-blotting检测表明,表达产物能与狂犬病病毒阳性血清发生特异性反应,出现单一反应带,扫描分析显示,表达产物占菌体总蛋白的23%,包涵体分离,纯化后,纯度达89%,上述结果为核蛋白在狂犬病基因免疫和免疫检测中的进一步应用奠定了基础。 相似文献